Anyone know oil boilers?

[Furbo]

We’ve got an elderly Trianco Eurostar which was working fine until we had it serviced. Now, it pops and thuds when it is running.

We’ve had the engineer back twice and he has been unable to resolve it. Today he has said we need to get a second opinion, because he cannot fix it.

Any ideas chaps?

[Voguely]

Where are you based? Not much idea about boilers myself, but I've been very impressed with the company we use to service ours (central Beds area, think they are based in north Herts) - pretty much took ours apart and put it back together last year and seemed very knowledgeable.

[Furbo]

Voguely said:

Where are you based? Not much idea about boilers myself, but I've been very impressed with the company we use to service ours (central Beds area, think they are based in north Herts) - pretty much took ours apart and put it back together last year and seemed very knowledgeable.

Nottingham

[boyse7en]

Have you run low on oil recently? Could be the oil line needs bleeding.

[Richard-D]

If it started directly after a service I'd be wondering if he's put the wrong nozzle in.

[Furbo]

Richard-D said:

If it started directly after a service I'd be wondering if he's put the wrong nozzle in.

He has reduced it one size an it's still doing it. But I suspect it is something like that.

[GasEngineer]

Can you tell whether the pops and thuds are coming from the burner or the pipework/heat exchanger jacket?

Could be "kettling" when the boiler heats up indicating air in the system or a circulation issue eg faulty heating pump.

[Furbo]

GasEngineer said:

Can you tell whether the pops and thuds are coming from the burner or the pipework/heat exchanger jacket?

Could be "kettling" when the boiler heats up indicating air in the system or a circulation issue eg faulty heating pump.

I can't.

The engineer said he thought pump. But it started the moment after he'd finished servicing it and I am not big on coincidences.

[Richard-D]

Furbo said:

GasEngineer said:

Can you tell whether the pops and thuds are coming from the burner or the pipework/heat exchanger jacket?

Could be "kettling" when the boiler heats up indicating air in the system or a circulation issue eg faulty heating pump.

I can't.

The engineer said he thought pump. But it started the moment after he'd finished servicing it and I am not big on coincidences.

You could be able to determine from the flue (If you watch the water vapour/mist at the outlet). If there's a pulse when it thumps it would confirm it's in the burner.

[JoshSm]

Depends what's been fiddled with.

First thing is to work out if it's the water boiling or something else.

Can you increase the pump speed and see if that changes anything? Setting the pump to a slow speed can trigger kettling and someone might have messed with it.

[Furbo]

He was at the pump yesterday so I imagine he will have tried speeding it up.

As for watching the flue, there are no visible emissions.

[GasEngineer]

Furbo said:

GasEngineer said:

Can you tell whether the pops and thuds are coming from the burner or the pipework/heat exchanger jacket?

Could be "kettling" when the boiler heats up indicating air in the system or a circulation issue eg faulty heating pump.

I can't.

The engineer said he thought pump. But it started the moment after he'd finished servicing it and I am not big on coincidences.

You could try listening at the boiler at the moment you switch the timer/thermostat off. If the same banging noise continues after the burner cuts off it's the system pump/pipework etc. If the noise stops immediately it's the burner.

[Furbo]

GasEngineer said:

Furbo said:

GasEngineer said:

Can you tell whether the pops and thuds are coming from the burner or the pipework/heat exchanger jacket?

Could be "kettling" when the boiler heats up indicating air in the system or a circulation issue eg faulty heating pump.

I can't.

The engineer said he thought pump. But it started the moment after he'd finished servicing it and I am not big on coincidences.

You could try listening at the boiler at the moment you switch the timer/thermostat off. If the same banging noise continues after the burner cuts off it's the system pump/pipework etc. If the noise stops immediately it's the burner.

Thanks, will try this.

[GasEngineer]

Any update OP?

[Murph7355]

Furbo said:

Richard-D said:

If it started directly after a service I'd be wondering if he's put the wrong nozzle in.

He has reduced it one size an it's still doing it. But I suspect it is something like that.

I wonder why he'd do that...

My guy just replaces like for like when it needs changing. If your boiler worked fine before the "service", why would it now need a change in nozzle size?

Is your tank low on oil/has it been recently?

[Furbo]

Murph7355 said:

Furbo said:

Richard-D said:

If it started directly after a service I'd be wondering if he's put the wrong nozzle in.

He has reduced it one size an it's still doing it. But I suspect it is something like that.

I wonder why he'd do that...

My guy just replaces like for like when it needs changing. If your boiler worked fine before the "service", why would it now need a change in nozzle size?

Is your tank low on oil/has it been recently?

No and no. It was 1/3 full and now it's very full, so I am very poor.

I wonder whether the previous engineer knew what he was doing and ha downsized the nozzle a couple of sizes. This bloke just fitted standard.

[GasEngineer]

You can adjust the output of the boiler by changing the nozzle size. Bigger nozzle lets more oil through = higher output.

Any update OP?

[Furbo]

GasEngineer said:

You can adjust the output of the boiler by changing the nozzle size. Bigger nozzle lets more oil through = higher output.

Any update OP?

OK so I did what you suggested, I got it running and then had someone turn it off. The banging stopped immediately.

I cannot be 100% because it is intermittent, and when I restarted it it was barely banging.

It's also making a slight whistling sound that it wasn't previously.

[Furbo]

I got another firm in to look at the boiler yesterday.

"Definitely the pump. The fact that it went wrong the same day it was serviced was a coincidence."

They fitted a new Brittherm pump. It is just as bad.

"Must need a power flush".

"You said it was the pump".

"....errrrrr.... or power flush".

Added to this, when the pump started at 05:30 this morning it sounded like a 747 engine. I was up in the loft before 06:00 turning it down.

I have currently got it running on hot water only. That surely means a power flush is not the answer?

[OutInTheShed]

I'd suggest you need a decent heating engineer who will look a bit deeper into what's going on.

Saying 'it needs a flush' is suggesting low water flow rate.
You should be able to diagnose that because the flow temp will rise quickly.

A noisy circulator pump often means air in the circuit.


Is there a magnetic filter? If not, adding one can only help.

Has the system been drained? How foul was the water?

If it's been run for years with no inhibitor a clean may be worthwhile.
A power flush may be cost effective, because faffing with draining and filling and bleeding can absorb a lot of man hours.

Personally I would drain it, fit a mag filter and rinse it a couple of times as a starting point, then add inhibitor if it's behaving or consider the next move if it's not.